Predictive factors for moderate or severe exacerbations in asthma patients receiving outpatient care

Characterization of Moderate and Severe Asthma Exacerbations in the CAPTAIN Study

BACKGROUND

Limited data exist on the relative impact of moderate and severe exacerbations on asthma control and impairment.

OBJECTIVE

To explore data from the CAPTAIN trial to evaluate the relationship between first moderate or severe exacerbation and changes in lung function, symptoms, physical activity limitation scores, and short-acting β2-agonist (SABA) usage to determine the clinical relevance of moderate events.

METHODS

CAPTAIN was a phase IIIA 24- to 52-week, multicenter, international, randomized controlled trial evaluating efficacy and safety of fluticasone furoate/umeclidinium/vilanterol (FF/UMEC/VI) versus FF/VI in patients with uncontrolled asthma on inhaled corticosteroid/long-acting β2-agonist. Outcomes reported include first postrandomization exacerbation event by severity (wk 1-52), frequency and duration of moderate and severe exacerbations, and time course of changes over ± 14-day peri-exacerbation period for lung function, symptoms, limitations, and SABA use.

RESULTS

Of the intent-to-treat population (n = 2,436), 550 patients (23%) continued to 52 weeks. There were 529 moderate and 546 severe exacerbations. Lung function changes were similar, but symptom, physical activity limitation scores, and SABA use were higher, for severe versus moderate exacerbations. Lung function decline preceded increases in symptom, physical activity limitation scores, and SABA use, irrespective of exacerbation severity. Lung function variables, limitation scores, and SABA use returned to pre-exacerbation baseline after approximately 8 to 12 days for both exacerbation severities.

CONCLUSIONS

Whereas severe events were associated with greater impact on symptoms, physical activity limitations, and SABA use, onset and time to resolution were generally similar for moderate and severe events. Both exacerbation severities represent clinically important deteriorations comprising clinical and functional changes.

Impact of Clinical Characteristics and Biomarkers on Asthma Impairment and Risk Questionnaire Exacerbation Prediction Ability

BACKGROUND

Complex models combining impairment-based control assessments with clinical characteristics and biomarkers have been developed to predict asthma exacerbations. The composite Asthma Impairment and Risk Questionnaire (AIRQ) with adjustments for demographics (age, sex, race, and body mass index) predicts 12-month exacerbation occurrence similarly to these more complex models.

OBJECTIVE

To examine whether AIRQ exacerbation prediction is enhanced when models are adjusted for a wider range of clinical characteristics and biomarkers.

METHODS

Patients aged 12 years and older completed monthly online surveys regarding exacerbation-related oral corticosteroid use, emergency department or urgent care visits, and hospitalizations. Univariate logistic regressions to predict exacerbations were performed with sociodemographics, comorbidities, exacerbation history, lung function, blood eosinophils, IgE, and FeNO. Significant (P ≤ .05) variables were included in multivariable logistic regressions with and without AIRQ control categories to predict 12-month exacerbations (log odds ratio [95% Wald confidence interval]). Model performances were compared.

RESULTS

Over 12 months, 1,070 patients (70% female; mean [SD] age, 43.9 [19.4] years; 22% non-White; body mass index [SD], 30.6 [8.7]) completed one or more survey (mean [SD], 10.5 [2.8] surveys). In the multivariable analysis, AIRQ control category adjusted for significant clinical characteristics and biomarkers was predictive of one or more exacerbations: odds ratio (95% CI) not well-controlled versus well-controlled: 1.93 (1.41-2.62), very poorly controlled versus well-controlled: 3.81 (2.65-5.47). Receiver operating characteristic area under the curve (AUC) for this more complex model of exacerbation prediction (AUC = 0.72) did not differ from AIRQ (AUC = 0.70). Models with AIRQ performed better than those without AIRQ (AUC = 0.67; P < .05).

CONCLUSION

Costly and time-consuming complex modeling with clinical characteristics and biomarkers does not enhance the strong exacerbation prediction ability of AIRQ.

Development and validation of a claims-based algorithm to identify moderate exacerbations in patients with asthma treated in the US

INTRODUCTION

Definitions of moderate asthma exacerbation have been inconsistent, making their economic burden difficult to assess. An algorithm to accurately identify moderate exacerbations from claims data is needed.

METHODS

A retrospective cohort study of Reliant Medical Group patients aged ≥18 years, with ≥1 prescription claim for inhaled corticosteroid/long-acting β2-agonist, and ≥1 medical claim with a diagnosis code for asthma was conducted. The objective was to refine current algorithms to identify moderate exacerbations in claims data and assess the refined algorithm's performance. Positive and negative predictive values (PPV and NPV) were assessed via chart review of 150 moderate exacerbations events and 50 patients without exacerbations. Sensitivity analyses assessed alternative algorithms and compared healthcare resource utilization (HRU) between algorithm-identified patients (claims group) and those confirmed by chart review (confirmed group) to have experienced a moderate exacerbation.

RESULTS

Algorithm-identified moderate exacerbations were: visit of ≤1 day with an asthma exacerbation diagnosis OR visit of ≤1 day with selected asthma diagnoses AND ≥1 respiratory pharmacy claim, excluding systemic corticosteroids, within 14 days after the first claim. The algorithm's PPV was 42%; the NPV was 78%. HRU was similar for both groups.

CONCLUSION

This algorithm identified potential moderate exacerbations from claims data; however, the modest PPV underscores its limitations in identifying moderate exacerbations, although performance was partially due to identification of previously unidentified severe exacerbations. Application of this algorithm in future claims-based studies may help quantify the economic burden of moderate and severe exacerbations in asthma when an algorithm identifying severe exacerbations is applied first.

Effect of Individual Patient Characteristics and Treatment Choices on Reliever Medication Use in Moderate-Severe Asthma: A Poisson Analysis of Randomised Clinical Trials

INTRODUCTION

Even though increased use of reliever medication, including short-acting beta agonists (SABA), provides an indirect measure of symptom worsening, there have been limited efforts to assess how different patterns of reliever use correlate with symptom control and future risk of exacerbations. Here, we evaluate the effect of individual baseline characteristics on reliever use in patients with moderate-severe asthma on regular maintenance therapy with fluticasone propionate (FP) or combination therapy with fluticasone propionate/salmeterol (FP/SAL) or budesonide/formoterol (BUD/FOR).

METHODS

A drug-disease model describing the number of 24-h puffs and overnight occasions was developed with data from five clinical studies (N = 6212). The model was implemented using a nonlinear mixed effects approach and a Poisson function, considering clinical and demographic baseline characteristics. Goodness of fit and model predictive performance were assessed. Heatmaps were created to summarise the effect of concurrent baseline factors on reliever utilisation.

RESULTS

The final model accurately described individual patterns of reliever use, which is significantly increased with time since diagnosis, smoking, higher Asthma Control Questionnaire (ACQ-5) score and higher body mass index (BMI) at baseline. Whilst the number of puffs decreases slowly after an initial drop relative to the start of treatment, exacerbating patients utilise significantly more reliever than those who do not exacerbate. The mean effect of FP/SAL (median dose: 250/50 μg BID) on reliever use was slightly higher than that of BUD/FOR (median dose: 160/4.5 μg BID), i.e. a 75.3% vs 69.3% reduction in reliever use, respectively.

CONCLUSIONS

The availability of individual-level patient data in conjunction with a parametric approach enabled the characterisation of interindividual differences in the patterns of reliever use in patients with moderate-severe asthma. Taken together, individual demographic and clinical characteristics, as well as exacerbation history, can be considered an indicator of the degree of asthma control. High SABA reliever use suggests suboptimal clinical management of patients on maintenance therapy.

Biologics in Severe Eosinophilic Asthma: Three-Year Follow-Up in a SANI Single Center

Introduction: Biologic drugs have dramatically improved severe eosinophilic asthma (SEA) outcomes. Our aim was to evaluate the long-term efficacy of biological therapy in SEA in a real-life setting and to identify the predictors for switching to another biological drug in patients with poor asthma control. The outcomes for efficacy were decreased annual exacerbations (AE) and improved asthma control test (ACT). Methods: In 90 SEA patients being treated with a biological drug, clinical examination, ACT, blood eosinophils count and spirometry were assessed before (T0) and after 6 (T1), 12 (T2), 24 (T3) and 36 (T4) months from the start of biological therapy. Patients were considered responders (R) or non-responders (NR) to biologics depending on whether or not they had less than two AE and a 20% increase in the ACT after 12 months of treatment. Results: 75% of the patients were R, 25% NR. In R patients, biological therapy add-on was followed by significant improvement in AE and ACT throughout the whole follow-up period. The percentage of patients on oral corticosteroids (OCS) dropped from 40% to 12%. By contrast, the NR patients were shifted to another biological drug after 12 months of therapy, as they still had high AE and nearly unchanged ACT; 40% of them still needed OCS treatment. The predictors of switching to another biological drug were three or more AE, ACT below 17, nasal polyposis and former smoking (p < 0.05). In NR, the shift to another biological drug was followed by a significant decrease in AE and an increase in the ACT. Discussion: This real-life study confirms the long-term efficacy of biologics in most SEA patients and indicates that even in non-responders to a first biological drug, it is worth trying a second one. It is hoped that the availability of additional biologics with different targets will help improve the personalization of SEA therapy.

[The management of asthma as a chronic inflammatory disease and global health problem: A position paper from the scientific societies]

Asthma is the most prevalent respiratory disease worldwide and it can affect people of all ages and is potentially fatal. Today, maintenance treatments are available that are effective in most patients, yet a significant proportion have poorly controlled disease, despite the resources on offer. This document, endorsed by members of the Spanish medical societies involved in the treatment of asthma, is intended to draw the attention of society and professionals to this problem in Spain. It focuses on the clinical, diagnostic and therapeutic aspects of asthma, and proposes some actions for improvement as regards patients and healthcare professionals which, in view of the current results arising from inadequate asthma control, might be beneficial to improve outcomes for both patients and public health.

Development and validation of an asthma exacerbation prediction model using electronic health record (EHR) data

Objective: Asthma exacerbations are associated with significant morbidity, mortality, and cost. Accurately identifying asthma patients at risk for exacerbation is essential. We sought to develop a risk prediction tool based on routinely collected data from electronic health records (EHRs).Methods: From a repository of EHRs data, we extracted structured data for gender, race, ethnicity, smoking status, use of asthma medications, environmental allergy testing BMI status, and Asthma Control Test scores (ACT). A subgroup of this population of patients with asthma that had available prescription fill data was identified, which formed the primary population for analysis. Asthma exacerbation was defined as asthma-related hospitalization, urgent/emergent visit or oral steroid use over a 12-month period. Univariable and multivariable statistical analysis was completed to identify factors associated with exacerbation. We developed and tested a risk prediction model based on the multivariable analysis.Results: We identified 37,675 patients with asthma. Of those, 1,787 patients with asthma and fill data were identified, and 979 (54.8%) of them experienced an exacerbation. In the multivariable analysis, smoking (OR = 1.69, CI: 1.08-2.64), allergy testing (OR = 2.40, CI: 1.54-3.73), obesity (OR = 1.66, CI: 1.29-2.12), and ACT score reflecting uncontrolled asthma (OR = 1.66, CI: 1.10-2.29) were associated with increased risk of exacerbation. The area-under-the-curve (AUC) of our model in a combined derivation and validation cohort was 0.67.Conclusion: Despite use of rigorous methodology, we were unable to produce a predictive model with an acceptable degree of accuracy and AUC to be clinically useful.

High ACT score is not sufficient to reduce the risk of asthma exacerbations in asthma with low lung function

BACKGROUND

Low forced expiratory volume in 1 s (FEV₁) is a risk factor for asthma exacerbations (AEs). We aimed to determine if asthma control could reduce the future risk of AEs in patients with low FEV₁. This study was conducted to evaluate the future risks of AEs within six months according to Asthma Control Test™ (ACT) score and FEV₁.

METHODS

A total of 565 patients with asthma were enrolled from the COREA cohort. The ACT score, lung function test, and number of AEs were assessed at baseline, three-month follow-up, and six-month follow-up with conventional asthma treatments by asthma specialists in real clinical settings.

RESULTS

Female sex, low ACT score, low FEV₁, low FVC, and AE history in the previous three months were related with increased AEs within six months. AEs during six-month follow-up occurred in 24% of patients with ACT <20 and FEV₁ < 60% at baseline. Among patients with an ACT score ≥20, 3.4% of patients with an FEV₁ < 2.16 L and 9.8% of patients with FEV₁ ≥ 2.16 L had experienced AEs (P = 0.01), although no differences were observed in the presence of AEs within six months according to the predicted FEV₁ (FEV₁ ≥ 60% vs. FEV₁ < 60%, 5.66% vs. 8.51%, P = 0.65).

CONCLUSION

Patient with low FEV₁ seemed to show higher risk of AEs than those with near-normal FEV₁ despite ACT score ≥20 and asthma treatments. Therefore, treatment strategies that prevent AEs are needed in high-risk asthmatic patients.